American officials say that a U.S. soldier in Afghanistan walked off a base in the predawn hours this morning and began shooting at civilian homes in the southern province of Kandahar. Initial reports say 15 civilians are dead, including women and children. Relations between the United States and Afghanistan had been slowly returning to normal after last month's accidental burning of the Quran at an American military base. But this morning's news may erase that progress.

Here to tell us more about the incident and other developments in Afghanistan is NPR's Kabul bureau chief Quil Lawrence. Quil, good morning.

QUIL LAWRENCE, BYLINE: Good morning, Linda.

WERTHEIMER: So, what do we know about this morning's shootings in Kandahar?

LAWRENCE: The details are still a little bit sketchy. Afghan and U.S. sources say a soldier in the Panjwai District of Kandahar walked off a base by himself, started this shooting spree, going house to house. And the dead may include women and children. This was at about 3 A.M. local time, as you said before dawn in the dark. After the killings, the soldier surrendered himself to his superiors back at the base.

Panjwai was a Taliban stronghold but it's now more or less under Afghan government control after the U.S. troops surged drove out insurgents over the last year and a half. I was able to drive out to Panjwai last fall, which is remarkable that that was at all possible but it was still very tense there. We don't know really what the motives were, what might've triggered this incident.

WERTHEIMER: Well, as we mentioned, the passions were cooling after the accidental burning of the Quran by U.S. soldiers, and of the riots and then the shootings that followed that. Is it possible the events are linked?

LAWRENCE: We don't know yet. As you say, there were these riots last month were many, many Afghans were killed in clashes with police. There were also six Americans killed by Afghan soldiers - or Afghan soldiers turned their guns on their American trainers - their allies. There was one of these cases in Kandahar. It wasn't in the same district where the shooting took place today, so it wouldn't appear to be closely linked in that way. These sort of cases have been on the rise.

Now in 2010, there was also a case in the neighboring province of Zabul, where a group of rogue American soldiers apparently killed Afghan civilians for sport. And the apparent ringleader of that group was convicted in the U.S. last November on three counts of murder. So it does seem, in any case, that after 10 years Americans and Afghans still have a lack of trust and understanding between these two military forces.

LAWRENCE: Yes, an Afghan government delegation visited five Taliban prisoners in Guantanamo and got their consent to be released to sort of house arrest in the Gulf State of Qatar. That would be a confidence-building measure towards the beginnings of peace talks that might be held there. The Taliban might in turn release a U.S. soldier that they've held since 2009.

The larger obstacle really to releasing these prisoners from Guantanamo would be getting congressional approval. The White House says that they can't release prisoners without congressional approval. And certainly in an election year, they might want to get some political cover before they did that.

WERTHEIMER: So, taking all these things together, how does this affect U.S.-Afghan relations right now?

LAWRENCE: Well, we had just been recovering from what people were calling the lowest point in U.S.-Afghan relations. People had just been getting back to meetings and getting off lockdown after the security situation. We haven't seen the ripple effect across the country - the news is just breaking out. But people here are very worried that this could undo the progress that was made in the last couple of weeks.